CHONBURI, Thailand –Lexi Thompson gets lucky number seven in Thailand.

Thompson captured her seventh career win on the LPGA Tour on Sunday at the Honda LPGA Thailand. With her victory, Thompson became not only the first American to win in the event’s 10-year history, but is also expected to overtake Stacy Lewis as the top-ranked American in the world.

Entering the week, world No.4 Thompson was projected to replace Lewis as world No.3 should she win and Lewis finish in a tie for second or worse. Lewis, who has held the top spot for the past 195 weeks, finished tied for 35th in Thailand. Thompson would become just the sixth player to own the title of top-ranked American since the inception of the women’s rankings in 2006.

The 21-year-old took command early in the week with an opening round 8-under par, 64 to take the outright lead in round one.

Despite scrambling to a second round even par, 72, Thompson cruised on the weekend, posting 64 again on Saturday to take a four stroke lead entering the final round and closing with a 4-under par, 68 to win by six-strokes ahead of In Gee Chun.

In many ways, Thompson put on the best performance of her career this week, posting her lowest winning score on Tour at 20-under par for the championship with a six-stroke victory, her largest margin of victory on Tour. Her win in Thailand marks her third victory since July, having won twice in 2015 at the Meijer LPGA Classic and LPGA KEB HanaBank Championship.